Inside tubing cutter



July 16, 1940. E. E. ANDERSON 2,208,011

INSIDE TUBING CUTTER Filed Aug. 14, 1939 2 Sheets-Sheet l E. E. ANDERSONINS IDE TUBING CUTTER July 16, 1940.

Filed Aug. 14, 1939 2 Sheds-Shree?I 2 I Patented July 16, 1940 2,208,011INSIDE TUBING CUTTER Ernest E. Anderson, Oklahoma City, Okla., as-

signor to Baash-Ross Tool Company,

Los

AngeleaCalif., a corporation of California Application April 14, 1939,Serial No. 267,875

l2 Claims.. (Cl. 164-037) This invention relates to a well tool andrelates more particularly to a tool for cutting tubing, drill pipe,casing and other tubularobjects in wells. A general object of thisinvention 5 is to provide a well tool of the character referred to thatis simple and sturdy in construction and that is positive and dependablein operation.

Tools known as inside cutters are employed in wells to cut or severtubing, casing, drill pipe,

` etc. to facilitate their removal from the wells. In operating thecutting tools it is sometimes impossible to determine when the cut iscompleted and the pipe or tubing is severed. Following the cuttingoperation an attempt is usually made to withdraw the severed portion ofthe pipe or tubing from the well. If it is found that the severedportion of the pipe or tubing cannot be pulled from thewell the successof the cutting operation cannot be determined.

Another object of this invention is to provide an inside cutting `toolthat provides a denite signal or indication at the completion of thecutting operation to give positive assurance that the pipe or tubing hasbeen fully cut or severed.

2.3 Another object of this invention is to provide an inside cutterembodying cutters or knives that are fully andV automatically retractedat the completion of the cutting operation, but not until the completionof the vcutting operation, to relieve the resistance to rotation of theoperating string thereby indicating to the operator that the cuttingoperation is completed.

Another object of this invention is to provide an inside cutter that issuch that the operator may keep informed of the extent of projection cithe cutters and therefore may be advised of the progress of the cuttingoperation.

Another object of the invention is to provide a cutting tool of'thecharacter mentioned em- 40 bodying novel means for evenly and smoothlyadvancing or extending the cutters outwardly as the operating string isrotated.

Another object of this invention is to provide a cutting tool of thecharacter mentioned that may be easily and inexpensively conditioned tocut tubular objects of different diameters and of differentWall'thicknesses.

The various objects and features of my inven- `tion will be fullyunderstood from the following to detailed description oi a typicalpreferred form and application of the invention, `throughout whichdescription reference is made to the'accompanying drawings, in which:

Fig. l is a side elevation of the tool of the :it invention in positionin a tubing, showingthe tubing in longitudinal cross section. Fig. 2 isan enlarged longitudinal detailed sectional view of the upper portion ofthe tool with the parts in the unactuated positions and illustrating aportion of the tool in side elevation. Fig. 3 isv 5 an enlargedlongitudinal detailed sectional view of the lower portion of the toolillustrating the holding means in the actuated condition. Fig. 4 is aview similar to Fig. 2 illustrating the mandrel in side elevation andshowing the cutters lo in a partially projected condition. Fig. 5 4is anenlarged transverse detailed sectional view taken as indicated by line5-5 on Fig. 2. Fig. 6is an enlarged horizontal detailed sectional viewtaken as indicated by line 6-6 on Fig. 4. Fig. 7 is an .lo enlargedhorizontal detailed sectional view taken fragmentary longitudinaldetailed sectional view illustrating the manner in which the cuttersretract above the actuating ribs at the completion 2o of the cuttingoperation and Figs. 9 and 10 are enlarged horizontal detailed sectionalviews taken as indicated by lines 9 9 and IIl--IlL respectively, on Fig.1.

I will herein refer to the device of the present 25 invention as atubing cutter and will describe the tool as operating to cut a tubing ina well. The invention may be embodied in tools for cutting other tubularobjects, for example, drill pipe, well casing, etc., and it is to beunderstood 3o thatthe invention is not to be construed as limited orrestricted to the specic form or application herein described.

The inside cutter of the present invention illustrated in the drawingsmay be said to com- 35 prise, generally, a body IU, projectable knivesor cutters I I carried by the body I0, a threaded mandrel 4I2 extendingthrough the body I5 and operable to actuate the cutters II, a nut I3having threaded cooperation with 'the mandrel I2 40 and releasable meansI4 for holding the nut I3 against rotation whereby rotationof themandrel v I2 projects the cutters II.

The body II) is an elongate tubular member or assembly adapted to extendinto the tubing T 45 with suitable clearance. In the preferredconstruction the body I0 comprises two sections, namely, an uppersection I5 and a lower section I5. The sections I5 and IB are connectedby spaced longitudinal screws I1 passed through 50 openings I8 in theupper section I5 and threaded into sockets I9 in the lower section I6.The opposing ends of the connected body sections I5 and I6 are spacedapart to leave a gap orspace for the cutters II. The two body sectionsI5 55 and I6 may be cylindrical and of uniform diameter. A pin 2@ ofreduced diameter is provided on the lower end of the lower body sectionI6.

The cutters II are projectable from the body IE! and are operable byrotation of the body to cut through the tubing T. In the preferred formof the invention there is a plurality of circumferentially spacedcutters `II provided in the space between the two body sections I5 andI6. As illustrated in the drawings, there may be three like cutters II.`The cutters II are longitudinally curved and are provided at their outerfree` corners with projecting sharpened blades or cutting parts 2i. Thecutters II are supported to pivot about vertical axes. Openings 22 inthe inner parts of the cutters II may receive the above mentioned screwsI'I vwhereby the screws serve to pivotally mount the cutters II. cuttersil are normally retracted to be entirely Within the space between thetwo body sections I5 and I6. `Y The mandrel I2 is Y an elongate memberadapted to be connected with the lower end of a well string or operatingstring S. The mandrel I2 passes downwardly through the tubular bodysections I5 and SII with suitable clearance and continues beyond thebody to cooperate with the nut I3 and tovcarry the means Ill as will besubsequently described. In accordance with the in vention the portion ofthe mandrel IE extending through the lower body section It and the nutIt is threaded. The thread S on the mandrel I2 is continuous and has agradual or slight pitch. A suitable guide member or head23 may beprovided on the'extreme lower end of the mandrel I2. v

The mandrel -I 2 r carries parts for cooperating with the cutters Il toeffectthe projection of the cutters. A plurality of longitudinallyextending tapered splines or ribs 2li is provided on the `mandrel I2.Th-e ribs 'fill are circumferentiallyV spaced about the mandrel I2 'andthere is a rib 265 for engaging each cutter II. The ribs 2d are ofsubstantial length and their outer surfaces or edges 2li are curved orrounded to substantially conform to the inner edges of the cutters II.The outer surfaces 25 of the ribs 2d slope downwardly and inwardlyrelative to the longitudinal axis of the mandrel I2. Itis preferredto'removably securethe ribs 2d to the mandrel I 2 whereby they may bereplaced by ribs capable of projecting the cutters I I dierent mandrelI2 and may be temporaryor"detachablysecured in the groovesr by weldingor the like.

With the parts in the initial or normal posi-y f tions the ribs 243extend into slotsl in the upper body'section I5. The slots 2l' areadapted to re'- ceiveor vpass the ribs 2li with suitable clearance andthe cooperation of the'sides of the ribs 2li withk the side wallskof theslots 2 may assist in transmitting 'rotationfrom the mandrel I2 to thebody 'It'. Slots ZIl are provided in the lower body section'lt toreceive the ribs 2d during the` actuationof the tool. The slots 28 areadapted to freely receive the ribs 2d and the engagementof Athe ribswith the side walls of the slots 2t may assist in transmitting turningforces from the mandrel I2 to the body I0. TheV outer walls or bottomwalls of the slots 28 may taper completion of thecutting operation tolimit the downward'travel ofy the ribs. f

The

. erably spring means.

In accordance with the invention the tapered ribs 2d are operable toproject the cutters II a distance sufficiently great to completely cutthrough the wall of the tubing T. 1t will be understood how the inclinedsurfaces 2li of the ribs 2@ cooperate with the cutters II duringdownward movement of the mandrel I2 relative to the body I3 to feed orproject the cutters II. The parts are related and proportioned so thatthe upper ends of the ribs 2d pass downwardly beyond the cutters I Isimultaneously with or immediately following the completion of the cut.

The invention provides means for automatically returning the cutters IIto their retracted positions at the completion of the cut orgwhen theribs E@ pass below the cutters I I. The means for restoring the knivesor cutters II are prefln the construction illustrated verticallyarranged leaf springs 33 are se- Curedto the upper body section I5 andextend downwardly to have their lower parts bear inwardly against theouter sides of the pivoted cutters II. Nhen the upper ends of the ribs 2pass-'the cutters II at or immediately following the completion of thecut the springs 33 pivot the knives or cutters I I inwardly to theretracted positions illustratedin Figs. 4 and 5 of the drawings, wherethey lie against the mandrel I2. The retraction of the cutters Il by thesprings 33 of course fully disengags the cutters from the tubing T.'Upon'the retraction of the cutters II from the tubing T, at thecompletion of the cut, substantially all resistance to rotation. of theoperating string S is relieved indicating to the operator that the cuthas been completed.

The nut I3 has threaded engagement with the mandrel I2 and is rotatablyconnected with the body It whereby rotation of the mandrel relative to`the nut feeds the'mandrel longitudinally toeect the actuation of thecutters I I. The nut I3 is preferably provided at one end of the bodyIII. "In the preferred construction illustrated the nut I3 is at thelower end of the body` III." A socket 29 in the upper end of the nutl I3receives the pin 2i! on the lower body section IS. Series of balls 3i)cooperate with opposing racesV 3i in the side and bottom walls of thesocket 29 and the side and bottom surfaces of the pin 2t to connect thebody II'I and nut I3 for free'f' relative rotation. A longitudinalopening 32 extends through the nut I3 to receive or pass the rmandrelI2. A thread is provided on the wall of the opening 32 to mate with thethread 9 on the mandrel I2.

The means II! is in the nature of a slip means and tail-piece meansIengageable with the interior of the tubing T to hold the nut I3 againstmovement whereby the threaded mandrel I2 may be rotated to project thepivoted cutters I I. The means It is located below the body I@ and isconnected with the nut I3. In the preferred construction the means Illincludes a sleeve 3d shiftably surrounding the mandrel I2 b-elow the nutI3. The upper portion of the sleeve 3d is threaded inthe' nut I3 so thatthe sleeve is rigid with the nut. It will be observed that the sleeve3ft is suspended from thebody III through the nut I 3. The sleeve -34has van intermediate portion 35 of enlarged diameter provided withdownwardly and inwardly inclined surfaces 36. Slips 3l are shiftable onthe -inclined surfaces 36. Dove-tailed tongue and groove connections 38are provided between the slips 3'! and the sleeve portions 35 wherebythe slips are held against (iii 'I'he outer lateral shifting anddisplacement. sides of the slips 3l have wickers or teeth 39 forgripping the inner surface of the tubing T.

The teeth 39ers grooved or cut vertically as well as horizontally sothat the slips 3l are operable to hold the sleeve 34 against turningmovement and longitudinal movement.

The means I4 further includes a spring assembly or tail-piece forcontrolling the slips 3T. Rings 44 and 4I are shiftable on the sleeve 34above and below its enlarged portion 35. Outwardly bowed leaf springs 42extend between and connect the rings 42 and 4I. The springs 42 areadapted to frictionally engage the interior of the l5 tubing T to resistmovement of the rings 4l) and 4I. Operative connections are providedbetween the rings 44 and 4I and the slips 3l whereby the engagement ofthe springs 42 with the tubing T resists movement of the slips 31.Fingers 43 20 and 44 extend longitudinally from the rings 45 and 4I,respectively, and pass through suitable grooves 45 in. the enlargedsleeve portion 35. The end portions of the ngers 43 and 44 cooperatewith notches 45 in the upper and lower ends of the slips 3l'. Thecooperation of the fingers 43 and 44 with the notches 42 is such thatthe springs 42 frictionally bearing in the tubing T resist movement ofthe slips 31 when the body Il! and the sleeve 34 are shifted to actuatethe slips. .l

Releasable means is provided to hold the sleeve 24 and the` springtail-piece assembly against relative longitudinal movement in arelationship where the slips 37 are retracted so that the tool may beeasily run through the well and freely entered in the tubing T. `Thismeans includes a control member 48 rotatably mounted on the lowerportion of the sleeve 34. A pin 49 may pass through an opening in themember 48 to coop- 4o crate with an annular groove 5i! in the sleeve 34.`The engagement of the pin 49 in the groove 55 prevents longitudinalshifting of the member 48 on the sleeve 34 but allows relative rotationbetween the sleeve and the member. A socket 5I is provided in the lowerend of the lower ring 4i and a pin 52 on the member 4B is releasablythreaded in the socket 5I. The threads of the socket 5I and the pin 52preferably have a much greater pitch than the threads 9 of the mandreli2 and the threads of the nut I3. A longitudinal slot 53 enters themember 48 from its lower end and a pin 54 on the mandrel I2 engages inthe slot 53. The pin 54 cooperating with the slot 53 is operable totransmit turning movement from the mandrel I2 to the member 48. When thepin 52 of the member 48 is threaded in the socket 5I the slips 3l are ina retracted condition clear of the interior of the tubing T. It will beunderstood how the mandrel I2 may be turned by means of the string S tothread the pin 52 from the socket 5I. In the use or operation of thetool of this invention the parts may be assembled as illustrated in Fig.l of the drawings and the mandrel I2 of may be connected with the stringSi preparatory to lowering the tool into the well. The pin 52 isinitially threaded in the socket 5l so that v the slips 3l are fullyretracted andthe springs 33 serve to hold knives or cutters Il in theirTo fully retracted positions. Thus the` tool may U be run through thewell without danger of the slips 3l or the knives l l interfering withits movement. When the tool or cutter has reached the correct orselected position in the tubing T the 75 string Si is rotated to threadthe pin 52 from the socket 5|. 'Ihe springs 42 cooperating with thetubing T resist turning of the ring 4I so that the pin 52 may be readilyunthreaded from the socket. When the mandrel I2 is rotated to unthreadthe pin 52 from the socket 5I the mandrel is threaded a short distancethrough the nut I3 and the ribs 24 may cause a slight outward pivotingof the cutters II. However, due to the marked difference in the pitch ofthe threads 9 on the man# drel I2 and the threads of the socket 5I andthe pin 52 the mandrel is threaded but a short distance at this time.Following the release of the pin 52 from the socket 5I the mandrel I2 islowered sothat the surfaces 36 cooperate with the slips 3l to actuatethem outwardly against the tubing T. The springs 42 frictionally bearingin the `tubing resist downward movement of the slips 3l when the mandrelis moved to actuate the slips. Following the settingof the slips 31 asjust described the string Si is rotated to thread the mandrel I2 downthrough the nut I3. The slips 3l gripping the interior of the tubing Tserve to hold the sleeve 34 and the nut I3 against rotation and downwardmovement while the mandrel is being threaded through the nut.

Downward threading of the mandrel I2 is accompanied by downward movementof the ribs 24 and is accompanied by rotation of the body Il). The ribs24 cooperate with the slots 21 and 28 to transmit the turning movementfrom the mandrel to the body I. The inclined surfaces 25 of the ribs 24cooperate with the knives or cutters il to feed or pivot the cuttersoutwardly. Thus the cutters Il carried by the rotating body IIJ are fedoutwardly against the interior of the tubing T as the mandrel I2 isthreaded down through the nut i3. The operator may be informed of thenumber of rotations of the mandrel I2 required to project the cutters IIa given distance andthe operator may in this manner be aware of thedepth of the cut and the condition of the tool at all times during itsoperation.

The rotation of the string S and the downward threading of the mandrelI2 is continued until the upper portions `of the ribs 24 are incooperation with the knives or cutters II at which time the knives willhave fully cut through the wall of the tubing T. Substantiallysimultaneously with the completion of the cut the upper ends of the ribs24 pass below the cutters II and the springs 33 suddenly retract thecutters from the tubing T. This retraction of the cutters Il `isaccompanied by the removal of substantially all resistance to rotationof the string Si and this informs the operator that the cut iscompleted. When the cut has been completed and the knives or cutters I Iretracted, as just described, the tool may be withdrawn from the well.When the string S` is raised the springs 42 cooperate with the tubing Tto resist upward movement of the slips 3l and the dove-tailedconnections 38 between the slips and the sleeve portion 35 causeretraction of the slips. The slips 3l and the knives II are fullyretracted when the tool `is the object, the body having argroove, acutter carried' by the body and projectable into cutting engagement withthe tubing, a nut member rotatably connected With the body, meansoperable to hold the nut member against movement, a mandrel threadedthrough the nut member, and a rib part on the mandrel engaging in thegroove to cause the body to rotate with the mandrel and cooperable withvthe cutter to project the cutter when the mandrel is threaded throughthe nut member.

2. A tool for cutting a tubular object in a Well comprising a bodyadapted to be rotated in the object, cutting means carried by the bodyfor projection into cutting engagement with the object, an inclinedpart-moved during rotation of the body to feedthe cutting meansoutwardly to make an annular cut through the wall of the object andhaving an end substantially normal to the direction of its movementmovable out of engagement with the cutting means at the comv pletion ofthe cut to free the cutting means for restoration, and means forrestoring the cutting means at the completion of the cut whereby sresistance to rotation of the body is relieved at the completion of thecut.

3. A tool for cutting a tubular object in a Well comprising a bodyadapted to be rotated in the object, a mandrel for rotating the body,means operable by rotation of the mandrel for moving the mandrellongitudinally relative to the body, cutting means carried by the bodyfor projection into cutting engagement with the object, an inclined parton the mandrel operable during said longitudinalmovement of the mandrelto feed the cutting means outwardly to make an annular cut through thewall of the object and having an end substantially normal to thedirection of said longitudinal movement movable out of engagement withthe cutting means at Athe completion of the cut freeing the cuttingmeans for restoration, and a spring for restoring the cutting means atthe completion of the cut whereby the resistance to rotation. of themandrel is relieved at the completion of the cut.'

4. A tool for cutting a tubular object in a well comprising a bodyadapted to be rotated in the object, cutting means carried by the bodyfor projection into cutting engagement with the object, a mandrel,thread means for advancing the mandrel when the same is rotated, and apart on the mandrel cooperable with the cutting means to project thesame .when the mandrel is advanced and adapted to move free of thecutting means by said advancement of the mandrel when the cut in theobject is completed.

5. A tool for cutting a tubular object in a well comprising a bodyadapted to be rotated in the object, cutting means carried by the bodyfor projection into cutting engagement with the object, a mandrel,thread means for advancing the mandrel when the same is rotated, and apart on the mandrel for rotating the body together with the mandrel andoperable to feed the cutting means outwardly to cut through the objectwhen the mandrel is advanced, and means for retracting the cutting meansfrom the object When the cut in the object is completed.

6. A tool for cutting a tubular object in a well4 comprising a bodyadapted to be entered into Vthe object, a cutter carried by the'body andprojectable into cutting engagement with the tubing, a nut memberrotatably connected with the body, means operable to grip the object tohold the nut member against movement, a mandrel having threadedengagement with the nut member to be fed longitudinally when rotated,and a part on the mandrel engageable With the cutter to project the sameas the mandrel is fed longitudinally and adapted to move past the cutterto free the same for retraction when the mandrel has been fed a givendistance.

7. A tool for cutting a tubular object in a Well comprising a bodyadapted to be entered into the object, a cutter carried by the body. andprojectable into cutting engagement with the tubing, a 'nut memberrotatably connected with the body, means operable to grip the object tohold the nut member against movement, a mandrel having threadedengagement with the nut member to be fed longitudinally When rotated,apart on the mandrel engageable with the cutter to project the same asthe mandrel is fed longitudinally and adapted to move past the cutter tofree the same forvretraction when the mandrel has been fed a givendistance, and spring means for retracting the cutter.

v8. A tool for' cutting a tubular object in a well comprising a bodyadapted to be entered into the object, a cutter carried by the body andprojectable into cutting engagement with the tubing, a nut memberrotatably connected with the body, means operable to grip the object tohold the nut member against movement, a mandrel having threadedengagement with the nut member toV be fed longitudinally when rotated,and a tapered longitudinal rib on the mandrel for projecting the cutteras the mandrel is fed longitudinally and adapted to move past lthecutter to free the same for retraction when the mandrel has been fed agiven distance.

9. A tool for cutting a tubular object in a well comprisinga bodyadapted to be entered into the object, a cutter carried by the body andprojectable into cutting engagement with the tubing, a nut memberrotatably connected with the body, means operable to grip the object tohold the nut member against movement, a mandrel having threadedengagement with the nut member to be fed longitudinally when rotated,and a tapered longitudinal rib on the mandrel for projecting thel cutteras the mandrel is fed longitudinally and adapted to move past the cutterto free the same for retraction when the mandrel has been fed a givendistance, the body having a groove shiftably receiving the rib to rotatewith the mandrel.

10. A tool for cutting a tubular object in a well comprising a bodyadapted to be entered.v into the object, a cutter carried by the bodyand projectable into cutting engagement with the tubing, a nut memberrotatably connected with the body, means operable to grip the object tohold the nut member against movement, a mandrel having threadedengagement with the nut member to be fed longitudinally when rotated,means initially holding the last mentioned means inoperative releasableby manipulation of the mandrel, and a part on the mandrel engageablewith the cutter to project the same as the mandrel is fed longitudinallyand adapted to move past the cutter to free the same for retraction whenthe mandrel has been fed a given distance.

11. A tool for cutting a tubular object in a well comprising a bodyadapted to be entered into the object, a cutter carried by the body and-projectable into 'cutting engagement with the tubing, a nut memberrotatably connected with the body, slipv means operable to grip theobject to hold the member against movement and to support the bodyagainst downward movement, a mandrel having threaded engagement with themember to be fed downwardly when rotated, a wedge part on the mandreloperable to project the cutter as the mandrel is fed downwardly andadapted to pass out of engagement with the cutter when the mandrel, hasbeen fed a given distance, and means for retracting the cutter when thewedge part leaves the same,

l2. A tool for cutting a tubular objectin a well comprising a bodyadapted to be entered into the object, a cutter carried by the body andprojectable into cutting engagement with the tubing, a nut memberrotatably connected with the body, slip means operable to grip theobject to hold the member against movement and to support the bodyagainst downward movement,

Y a releasable control for holding the slip means in a retractedcondition, a mandrel having threaded engagement with the member to befed downwardly when rotated, a wedge part on the mandrel operable toproject the cutter as the mandrel is fed downwardly and adapted to passout of engagement with the cutter when the mandrel has been fed a givendistance, and means for retracting the cutter when the wedge part leavesthe same.

ERNEST E. ANDERSON.

